Treatment of hydrocarbons



June ll', 1935.

c. THOMPSON Er 1m.y

TRETMEN'l` OF HYDROCARBONS IOriginal Filed July 23, 1931 .Sauk -..gpo

kownom/ Ecowvw/ 7 INVENToR/ I M ArroRNEYs /Wg @7W- NN n h@ @SS n Pnna Jane 11, 193s .UNITED STATE TREATMENT F Charles L. Thompson,

HYDROCARBONB Thomas S. Bacon, and

Joseph E. Bludworth, Eastland, Tex.. assignors, by menne assignments, to Hanlon-Buchanan,

Inc., a corporation of Delaware Application Jill! 23, 1931, Serial No. 552,610 Renewed March 20, 1935 18 Claims.

This invention relates to a method for the production of oxygen derivatives of hydrocarbons and it is useful in the production of desired substances by oxidation oi hydrocarbons, particularly in the production of methanol.

It has previously been proposed to eifect partial oxidation by heating hydrocarbons with a quan- *tity of oxygen insuicient to effect complete oxidation of the hydrocarbons and it has been l0 found that diiliculty is encountered in so controlling the reaction as to produce the desired oxidation product and to prevent decomposition or undesirable alteration oi' such desirable products as are produced.

In the practice of this invention the oxidizing of hydrocarbons resulting from the heating of a mixture of hydrocarbons with oxygen is so controlled by regulation of temperature, pressure,

relative proportions of substances present and du- 20 ration of influencesl tending to cause reaction, that substantial quantities of the desired product can be produced and protected against alteration in an operation that can be carried out on any scale and is commercially economical.

The principles involved in maintaining such control of the reaction that the desired product is produced and protected against alteration, may be applied to the production of various substances but they are described herein in connection with the production of methanol and valuable byproducts for the purpose of rendering this invention understandable, with the intention that this invention is not limited to the production of the products mentioned.

In the practice of this invention a hydrocarbon constituting the raw material is mixed in vapor phase with a lesser proportion by volume of oxygen and with a very much greater proportion by volume of diluent gases such as uncondensed reaction-products; and the mixture is heated, preferably under super-atmospheric pressure, to a temperature that initiates an exothermic reaction, and maintained at a reaction temperature for`a controlled period of time and thereafter cooled, the uncondensed vapors of the cooling operation preferably constituting the source of the uncondensed reaction-products which are mixed with the hydrocarbon and oxygen prior to the heating thereof. Uncondensed vapors returned culation vapors.

In the practice of this invention the control of the reaction to the end that the desired product is produced economically and in suillcient proportion and is protected against undesirable to the heating operation are herein called recir` alteration is important, `and numerous features oi this invention contribute separately and in combination to the maintenance of such control.I An important feature of this invention is that the volume oi.' diluent gases, such as recirculation vay pors, that are employed in the gas mixture entering the reaction chamber, is large. 'I'hese diluent gases do not contain any substantial proportion of free oxygen, and therefore regulation of the proportion of diluent gases provides means for effectively controlling and limiting to a low value the free-oxygen concentration in the reaction zone. In addition, the heat absorbing capacity of these gases is high, and the heat oi' reaction is absorbed by them with but a very slight rise in the temperature of the gases passing through the reaction zone, thereby making possible very close control of the temperature of the reaction zone.

A further feature is that the concentration of hydrocarbon in the vapor-mixture passing to the heating operation is relatively high, and the hydrocarbon content of that mixture consists mainly of unoxidizcd hydrocarbons in the uncondensed reaction vapors added to the mixture. By having an appreciable proportion of hydrocarbons in the recirculation vapors, and recirculating large volumes of uncondensed vapors, variations in the oxygen supply effect but slight variations in the proportion of oxygen in thevapors entering the heating operation.v A further feature of this invention is the comparatively long time during which the oxidation reaction is allowed to proceed. It appears that with the very low oxygen concentration employed, a very appreciable length of time is required for complete reaction at the minimum or relatively low reaction temperature employed. Preferably in the practice of this invention air is utilized as the source of oxygen and the nitrogen so introduced to the system acts as a diluent and reduces the percentage of oxygen in the total vapors passing to the heating operation. Moreover it appears that when atmospheric oxygen is employed, with consequent introduction of nitrogen into the system, substantially lower temperatures are required to initiate reaction and to elect the desired oxidation, thus indicating the probable existence of catalytic effect of the atmospheric nitrogen. vThe successful combination of these features makes possible the complete chemical combination of the free oxygen introduced, at temperatures below which substantial thermal decomposition, or pyrolysis, of the desired products' of reaction occurs.

In the practice of this invention, assuming that the oxidizing reaction will be carried on in a continuous operation, with fresh hydrocarbon and air continuously supplied to the mixture passing to the heating operation, the amount of air supplied to that mixture will be so limited that the oxygen contained therein will be less than sumcient to oxidize all of the supplied hydrocarbon into the desired product, and the uncondensed vapors of the reaction will therefore be rich in hydrocarbon, and the recirculation of relatively very large proportions of uncondensed vapors to the mixture passing to theheater will result in keeping the ratio of oxygen to hydrocarbon in that mixture as low as possible. Increase in the amount of air introduced will result in increased oxidation and in decreased concentration of hydrocarbon in the recycled vapors, thus impairing that control of the reaction which is 'effected by the use of low concentrations of 'oxygen and high concentration of hydrocarbon vapor.

Thus, in the practice of this invention the concentration of oxygen and the concentration of hydrocarbon in the reaction zone are carefully controlled and the ratio of oxygen to hydrocarbon is kept very low. These conditions facilitate such a control of the reaction as will promote productionfof the desired product and protect the desired product formed, but they require and also permit that the duration of the period at which the mixture is retained'at reaction temperature for the production of the desired substance shall be unusually long but will not undesirably alter the product formed. The desired proportions of oxygen and hydrocarbon in the gases passing to the heating operation are readily maintained by regulating the relative volumes of supplied air, supplied hydrocarbon and reclrculated reactionproducts, the proportion of hydrocarbon in such products being dependent upon the ratio of supplied hydrocarbon to supplied oxygen.

In the practice of this invention the temperature to which the mixture is heated in the heating operation should be as low as will initiate the oxidizing reaction, which condition is indicated by producton of heat, and steps should bev taken, such as withdrawing heat, o'r permitting its escape, from the reaction zone, that such production of heat does not result in temperatures producing undesirable effects. Such effects include the further or secondary oxidation of aliphatic oxygen derivatives of the character above mentioned with excessive formation of such products as oxides of carbon, water and the like. 'Ihe mixture in the reaction zone should be maintained at the desired temperature for a period of time that is long enough'to ensure that complete combination of the oxygen will occur.

In the practice of this invention production of desired compounds appears to increase with the pressure but there are pressures beyond which increase in production is not directly proportionate to increase in the pressure, and a pressure is chosen that is economically advantageous.

Preferably in the practice of this invention the mixture is completely formed prior to heating, and preferably the addition of hydrocarbon or of oxygen or of both to the heated vapors is avoided because such additions inevitably result in concentrations, prior to diffusion of the ingredients, which impair the control of the reaction and the efliciency of the process.

In the practice of this invention the employment of low oxygen concentration not only contributes to maintenance of such control as will lead to the production of the desired product and prevent undesirable alteration thereof, but an advantageous result is that such gases as are vented from the system to prevent undesirable rise of pressure therein are sufficiently rich in hydrocarbon to be used as a fuel.

Other and further features and advantages of this invention will appear from the following description of a specific example of thevapplication of this invention which is herein described for the purpose of assisting in the understanding thereof, but with the intention that this invention is not limited to the specific substances treated or products produced or conditions of operation stated and that this invention includes treatment in accordance with the principles herein set forth of other hydrocarbons and of mixtures of the same hydrocarbons in different proportions. With this understanding an example of the application of this invention is as follows:

In the accompanying drawing there is shown diagrammatically one arrangement of an apparatus whereby this invention may be practiced, together with various values of temperatures, pressures and proportions suitable to the operation now described.

In this example residue gas, remaining after the contacting of natural gas with mineral seal oil for the absorption in the oil of gasoline hydrocarbons contained in the gas, was the hydrocarbon employed and a typical analysis thereof was approximately as follows:

' Percent This gas was introduced through pipe I, meter 2 and pipe 3 to compressor 4 and for each thousand cubic feet so introduced to the system substantially 2200 cubic feet of air were introduced through pipe i, meter I and pipe to compressor 9. In compressors 4 and 9 pressure of the gas and air was raised to 350 pounds per square inch gauge pressure and the temperature of the compressed gas and air was raised bythe compression to between 200 F. and 350 F. The compressed gas was passed through pipe 5 to pipe I I and the compressed air was passed through pipe I0 to pipe II. Also, into pipe II there was introduced as hereinafter described approximately 60,000 cubic feet of uncondensed reaction vapors for each thousand feet ofA hydrocarbon" vapor supplied through pipe I.

This resulting mixture passed through pipe I2 into a mixing chamber Il, from which it was led by pipe I4 to heat exchanger 35, passing through pipe 36 in the heat exchanger, the approximate composition of the gas-mixture entering the heating operation being as follows:

Nitrogen 64.7

In heat exchanger 35 the temperature of the gases entering through pipe I4 was raised to between approximately 400'11'. and 600 F. by the absorption of heat from the hot products of reaction passed countercurrently through heat exchanger 35 by pipe 41. The temperature to which the gases are heated may be controlled by means of by-pass 49, controlled by valve 43, regulating the amount of hot gases admitted to theheat exchanger, and thereby regulating the temperature to which the cold gases ilowing into pipe 33 are heated. The heated gases leaving pipe 36 may flow directly through valves 31, 4I, and 43 and pipe I3 into reaction chamber I9. But in starting up the apparatus, valve 4I is closed, and the gases pass through valve 42 to heater I5, heated by burners I6 controlled by valve I1, where the gases are heated to reaction temperature, and then pass through valve 43 and pipe I3 to the reaction chamber I9. After the system has been brought to operating temperature, it may be advantageous to pass the heated vapors leaving pipe 36 through valve 35, by closing valve 3I. The heated vapors leaving valve 33 pass through pipe 39 to coil 40 placed in reaction chamber I9. 'I'he gases passing through coil 40 Aare heated slightly by the hot'reaction gases and at the same time serve to maintain a more constant temperature of the gases in the reaction chamber I9. The heated gases leaving coil 40 may be passed directly into reaction chamber I9 by closing valve 42 and opening valves 4I and 43, or may be passed through heater I5 where the gases are heated to reaction temperature by closing valve 4I and opening valves 42 and 43. A consideration of the drawing will show that the temperature of the gases entering reaction chamber I9 may be accurately controlled by the outlined system of heat exchange, or its obvious modifications. The reaction chamber I9 is preferably heat insulated by lagging 20 of any suitable type. `In reaction chamber I9 the reaction initiated by heating the mixture of gases increased the temperature to between approximately 600 F. and 4'700 F. The extent to which the temperature in reaction chamber I9 exceeds that in pipe I3 (preferably 90 F. or less) may be regulated by adjusting the thickness or effectiveness of the lagging 20 on reaction chamber I9 or by internal or external cooling of reaction chamber I9. The period of time during which the mixture remained in reaction chamber I9 was preferably longer than 5 seconds, and in the neighborhood of 20 seconds, the durration of this period being controllable by regulation of the volume of reaction chamber I9 relatively to the volume of mixed vapors passing therethrough.

When the gas mixture entering reaction chainber I9 contains a greater percentage of hydrocarbons heavier than methane, than is contained in the gas mixture last referred to, the temperature to which the mixture is heated before it enters the reaction chamber does not need to be as high as 600 F. but need only be suchtemperature as is necessary to initiate the reaction. In this example the iron apparatus employed and also the nitrogen present may exert, a catalytic effect on the reaction. While the temperature of the mixture entering the reaction chamber is maintained as low as possible buthigh enough to initiate the reaction, sufficient temperature will initiate an exothermic reaction that causes complete combination of the free oxygen present. Preferably control of the temperature within the reaction chamber should be such as to maintain that temperature slightly above the temperature of the vapors entering the ,reaction chamber. Preferably temperatures in the reaction chamber above about 900 F. are avoided, as such temperatures result in products which are normally less desirable. 'Ihe large amount of recycled vapors will assist in maintaining a uniform temperature in the reaction chamber and preventing large increases of temperature inasmuch as the reacting ingredients, due to the large volume of recirculation vapors, constitute but a minor proportion of the total vapors present in the reaction chamber.

vapors were withdrawn from reaction chamber I9 through pipe 44 and passed through valve 45 and through pipe 4'I in heat'exchanger 35. A portion of the gases in pipe 44 may be by-passed through pipe 49 and control valve 43. back to pipe 2i which leads from heat exchanger 35, thereby permitting control of the temperature of the heated vapors leaving heat exchanger 35 through pipe 36. The gases leaving pipe 41, in heat exchanger 35, and the gases passed through control valve 43, are passed through pipe 2| to condenser 22, cooled in any manner as by a spray from pipe 33 controlled by valve 34. The cooled Yproducts passed from the condenser through pipe 23 to separator 24. Uncondensed vapors were passed from separator 24 through pipe 25 and pipe 26 and meter 50 to compressor 2 1 from which compressed recirculation vapors were passed through pipe 23 into pipe II as above stated. Pipe 25 was provided with a relief valve 29 which passed into vent 30 a sufficient quantity of vapors to prevent the accumulation of undue pressure within the system. A typical example of the composition of the vapors passed through vent 30, at the rate of about 2660 cubic feet for each thousand cubic feet of gas passing into pipe I,

was approximately as follows:

Percent Methane f 22.5 Ethane 2.2 CO2 5.0 CO 3.2 Oxygen 0.0 Nitrogen--- 65.3 Hydrogen 1.8

under pressure conditions most favorable commercially.

This determination was made by a method of fractional distillation, as follows: A measured sample of the condensate was placed in a large flask with an excess of powdered lime, and the fraction boiling below the boiling point of water was removed by distillation and condensed. 'Ihis condensate was carefully refractionated. 'I'he amount of pure methyl alcohol was estimated from the boiling point curve, density curve, and refractive index curve of the product obtained from this final fractionation. Fractionation indicated that the crude methanol produced at the rate of 1.7 gallons per thousand cubic feet of gas suppliedwas between 80% and 95% pure methyl Cil alcohol while the remainder was composed chieny of acetone and ethyl alcohol.

The formaldehyde content was determined by titration. First. free acidity was determined by titration with standard caustic soda solution, and free acidity plus formaldehyde was determined by titration of a fresh sample with standard ammonia. Higher aldehydes were shown by fractionation to be present in the condensate.

As stated above this invention includes but is not limited to the details set out in the foregoing example, and this invention includes the application of the principles set out herein to the treatment of hydrocarbons other than those contained in the gas treated in the foregoing example, especially hydrocarbons obtained from natural gas, refinery gas, natural gasoline plant vapors, and mixtures thereof; and to the treatment of a mixture in widely different proportions of the same hydrocarbons that are contained in the gas treated in the foregoing example. And, the principlesherein' set out for the oxidation of hydrocarbons may be applied, within the spirit of this invention, to the treatment of any constituent, in a pure or substantially pure state of the vapors treated in the example herein described, e. g. pure or substantiay pure methane, ethane, propane,butane or pentane, the vapors of propane, butane and pentane producing large yields oi.' liquid products substantially different from those obtained in the example above described. In the same connection, the concentration of oxygen in the mixture passing to the reaction zone in the practice of this invention will be kept as low as consistent with the production of a commercially feasible quantity of the desired product in-the equipment employed, and the concentration of hydrocarbon will be kept low but far in excess of the oxygen present, and the lowest possible temperature will be employed that will initiate a reaction that will persist until 'complete combination of the oxygen, and increases of pressure will be limited to such increases as produce substantial increases in production commensurate with the cost of compression. Preferably the concentration of hydrocarbon in vapors passing to reaction will be determined by regulation of volume of recirculation, which usually will be relatively large and contain a proportion of hydrocarbon that is substantial and is determined by the rate of oxygen supply in that it decreases as the proportion of oxygen supplied to that system increases. In certain cases, and particularly in the production of methanol, especially when methanol is produced vfrom dry natural gas or from residue gas of the type referred to in the foregoing example, oxygen concentration will be between approximately 0.5% to 3% and preferably less than 1.5% in the vapors passing to the heating operation preliminary to the reaction. and hydrocarbon concentration in thosevapors will be between 10% and 40%, byvolume. The diluent gas in the vapors passing to the heating operation is preferably neutral, except as it may act catalytically, and this condition is met by the use of air for the supply of oxygen and the recycling of reaction products, the volume of air so fed to the system being ordinarily 1.5 to 4 times as great as the volume of fresh hydrocarbon vapor fed to the system and the volume of uncondensed reaction vapors so recycled being 25 to 100 times as great as the volume of such fresh hydrocarbon vapor. The reaction may be favorably affected by the carbon oxides and possible hydrogen in such products. Apparently a gauge pressure of 350 lbs. per square inch provides economic operation but the pressure may be higher, particularly when `hydrocarbons heavier than in the example set out above are supplied to the system.

In such case lower temperatures will initiate reaction. In connection with such low concentrations and temperatures care must be taken to maintain the mixture in the reaction zone long enough for complete reaction and a reaction period of 5 to 60 or more seconds is desirable. Other convenient sources of gas mixtures for oxidation in accordance with this invention are reilnery gases, the pop-oil' vapors of accumulator tanks used in condensing gasoline from natural gas or from still vapors of oll used to absorb gasoline from natural gas, and the pop-on vapors of rectifying towers used for stabilizing gasoline obtained Afrom natural gas or other hydrocarbon vapors.

While this invention is particularly suited to the production of methyl alcohol, and in the production of that substance is well suited to the use as raw materials of normally gaseous and low-boiling hydrocarbons such as occur in natural gas, in rei'lnery gas, or in natural gasoline plant vapors, and of mixtures of such hydrocarbons, it is to be understood that the application 'of the principles of this invention to the production of other substances and to the use of other raw materials falls within the spirit of this invention. It is to be understood that analyses and proportions given herein are in terms of vapor volume, corrected to standardl pressure and temperature conditions unless otherwise specified; and that this invention is vnot limited to the pressure and temperature conditions indicated on the drawing but includes those conditions and all other conditions indicated herein or falling within the spirit of this invention. References herein to uncondensed reactionproducts" are intended as references to vapors and gases which have been emitted from the 'reaction zone and` from which oxides of hydrocarbons and water have been condensed but which are otherwise substantially unaltered in composition. Such uncondensed reaction products will have substantially the same composition as thel vented gases.

We claim:

1. A process for producing aliphatic alcohols and other oxidation products from low-boiling hydrocarbons such as occur in one of the group consisting of natural gas, refinery gas, and natural gasoline plant vapors, and from mixtures oi.' such hydrocarbons, which comprises continu- 'ously forming a mixture of a fresh quantity of suchhydrocarbon in vapor form and a fresh quantity of air and a quantity of uncondensed reaction-products containing nitrogen and carbon oxides and a substantial proportion of unconverted hydrocarbons, said quantities being in such proportion that the mixture contains by volume 0.5% to 3% of .uncombined oxygen and to 40% of hydrocarbons and the remainder is composed mainly of nitrogen containing relatively smaller quantities of carbon oxides, heating the mixture while under pressure in excess of 200 pounds to a temperature not substantially in excess of 700 F., maintaining the mixture at substantially the temperature resulting from the reaction until combination of the free oxygen is substantially complete, cooling the resulting vapors, and utilizing the uncondensed vapors resulting from the cooling operation as the source of uncondensed 'reaction-products introduced ously forming a mixture of a. fresh quantity ofj such hydrocarbon in vapor form and a fresh quantity of free oxygen anda quantity of `uncondensed reaction-products containing a substantial proportion of unconverted hydrocarbons, said quantities being in such proportion that the mixture contains by volume 0.5% to 3% of uncombined oxygen and 10% to 40% of hydrocarbons and the remainder is composed, mainly of neutral gas and carbon oxides, heating the mixture while under pressure in excess of 200 pounds to a temperature not substantially in excess of 700 F. and substantially limited to that temperature which will initiate reaction, maintaining the mixture at substantially the temperature resulting from the reaction for a period of five to sixty seconds until combination of the free oxygen therein is substantially-complete, cooling the resulting vapors, and utilizing uncondensed vapors resulting from the cooling operation as the source of uncondensed reaction-products introduced into the mixture with said fresh quantities of hydrocarbon and oxygen.

3. A process for producing aliphatic alcohols and other oxidation products from low-boiling hydrocarbons such as occur in one ofthe group consisting of natural gas, refinery gas, and natural gasoline plant vapors, and from mixtures of such hydrocarbons, which comprises continuously forming -a mixture of a fresh quantity of such hydrocarbon in Avapor form and a -fresh quantity of air and a quantity of uncondensed reaction-products substantially free of free oxygen and containing nitrogen and carbon oxides and a. substantial proportion of unconverted hydrocarbons, said quantities being in such proportion that the mixture contains by volume 0.5% to 3% of uncombined oxygen and 10% to 40% of hydrocarbons and the remainder is composed mainly of nitrogen containing relatively smaller quantities of carbon oxides, heating the mixture While under pressure in excess of 200 pounds to a temperature not substantially in excess of '700 F., maintaining the mixture at substantially the temperature resulting from the reaction until combination of the free oxygen renders the mixture substantially free of freel oxygen, cooling the resulting vapors, and utilizing the uncondensed vapors resulting from the cooling operation' as the source of uncondensed reaction-products v introduced into the mixture with said fresh quantities of hydrocarbon and air.

4. A process for producing aliphatic alcohols and other oxidation products from low-boiling hydrocarbons such as occur in one of the group consisting of natural gas, refinery gas, and natural gasoline plant vapors, and from mixtures of such hydrocarbons, which comprises continuously forming a mixture of a fresh quantity of such hydrocarbon in vaporvform with 2 tol 3 times as great a volume of fresh air and 25 to ytimes as great a volume of uncondensed reaction products substantially free of free oxygen and containing substantial proportions of unconverted hydrocarbon and neutral gas, heating the mixture while under a* pressure in excess of 200 pounds to a temperature not substantially,`

in excess of 700 F. and substantially limited to that temperature which will initiate reaction, maintaining the mixture at a temperature as high as said last mentioned temperature and not substantially in excess of the temperature resulting from said reaction until combination of the free oxygen therein renders the mixture substantially free of free oxygen, cooling the resulting vapors, and utilizing the uncondensed vapors of the cooling operation asthe source of reaction-products introduced into the mixture with fresh quantities of hydrocarbon and air.

- 5. A process for producing aliphatic alcohols I and other oxidation products from low-boiling hydrocarbons such as occur in one of the group consisting of natural gas, renery gas, and na'- tural gasolineplant vapors, and from mixtures of such hydrocarbons, which comprises continuously forming a mixture of a fresh quantity of such hydrocarbon invapor form and a fresh quantity of free oxygen and a quantity of uncondensed reaction-products containing a substantial proportion of unconverted hydrocarbons, said quantities being in such proportion that the mixture contains by volume 0.5% to 3% of uncombined oxygen and 10% to 40% of hydrocarbons and the remainder is composed mainly of `neutral gas and carbon oxides, heating the mix- Y of free exygen, cooling the resulting vapors, and y utilizing uncondensed vapors resulting from the cooling operation as the source of uncondensed reaction-products introduced into the mixture with said fresh quantities of hydrocarbon and oxygen. Y

6. In the oxidation of hydrocarbons, the method as defined in claim 5, in which the hydrocarbon treated is a hydrocarbon of the parafln series, ina substantially pure state, having one to j five' carbon atoms.

7. A process for producing aliphatic alcohols and other oxidation products from low-boiling hydrocarbons such as occur in one of the group consisting of natural gas, refinery gas, and natural gasoline plantr vapors, and from mixtures of such hydrocarbons, which comprises continuously forming a mixture of a fresh quantity of such hydrocarbon in vapor form and a fresh quantity of free oxygen and a quantity` of uncondensed reaction-products containing a substantial proportion of unconverted hydrocarbons, said quantities being in such proportion that the mixture contains by volume 0.5% to 3% of uncombined oxygen and 10 to 40% of hydrocarbons and the remainder is composed mainly of neutral gas and carbon oxides, passing the mixture through a reaction zonel under pressure in excess of 200 pounds suciently slowly thatA -l not substantially in excess of 700v F; and limited substantially to "that temperature will :il il! 3.113.111 lprose sx1 1t: 1; noducui g1 lipipltilt l1 s1 .ediz-:niiet 1 1 1 m11 i1 more n mnatixtio 11 117011111111111.- t r': rtm1 :l: wr-mlibili! l I l 1 stcufcmairbm ,s .ornmni'nllvl 1l 111 amor: t :im: n.1 11i il cri-l 1- 1 n n1 11 .'c i; 1111111111111 11111 mndmcmzrbnsn 11,1 hnli: 1': :commas :c1

tural gasoline plant vapors, and from mixtures` of such hydrocarbons, which comprises continuously forming a mixturevof a fresh quantity of such hydrocarbon in vapor form and a fresh quantity of air and a quantity of uncondensed reaction-products containing nitrogen and carbon oxides and a substantial proportion of unconverted hydrocarbons, said quantities being in such proportion'that the`mixture contains by volume 0.5% to 3% of uncombined oxygen and 10% to 40% of hydrocarbons and the remainder is composed mainly of nitrogen containing relatively smaller quantities of carbon oxides, heating the mixture while under super-atmospheric pressure to a temperature not substantially in excess of 100 F., maintaining the mixture at substantially the temperature resulting from the reaction until combination ofthe free oxygen is substantially complete, cooling the resulting vapors, and utilizing the uncondensed vapors resulting from the cooling operation as the source of uncondensed reaction-products introduced 1l :drammi m 11i dim combined loxygen and 20% to 25% of hydrocarbon and the remainder of the mixture is composed mainly oinitrogen containing carbon oxides, heatingthe mixture under super-atmospheric pressure to a temperature in the neighborhood of 600 F. and sutlicient to initiate reaction, maintaining the mixture at a temperature as high asl said last-named temperatu/re/nd not substantially in excess of the temperature resulting from said reaction until combination of the free oxygen therein renders the mixture substantially free ofV oxygen, cooling the resulting vapors, and utilizing uncondensed vapors resulting from the cooling operation as the source of uncondensed reaction-products introduced into the mixture with said fresh quantities of hydrocarbon and air.`

11. vA process for producing aliphatic alcohols and .other oxidation products from low-boiling hydrocarbons such as occur in one of the group consisting of natural gas, renery gas, and natural gasoline plant vapors, and from mixtures of such hydrocarbons, which comprises continuously forming a mixture of a fresh, quantity of such hydrocarbon in vapor form and a fresh quantity of free oxygen and a quantity of uncondensed reaction-products containing a substantial Yproportion -of unconverted hydrocarbons, said quantities being in such proportion that the mixture contains byvolume 0.5% to 3% of un- I combined oxygenandI 10% to 40% of hydrocarbons and the remainder is composed mainly of neutralasndeoarbonfixide- ,na-Ssnmtheamin 1 1 1m: s; itlmnxti '1111. r eiucztirtlo: m ma 1u mi'mpseumrn 1i J .11:remmersatit:mslbanunxiilsltmlsmccssam M'Mli .1140i l 1 1 mnuriui't v1 tc f rest: 11111 .sin m11 a1 mnuhltw 111m 71h mmm-1 1 1 l animale c: '1 rommirm-'omdust s uhaitahlimiurl si 1 to .i r .11m Lsdi 12 :nom lwhi le: aiaizaininn 11tl 11:11 1t :tompecmtm 1 ,l ninixmre maintains vt Nomine: s) W51 l c1 all i: l1 nim-u l' :Miata :nations 1: lnintamninlr time: untuinsl 0:1 1a: sai 7 51 1L zone at a temperature as high as said last-mentioned temperature and not substantially in excess oi.' the temperature resulting from said reaction, cooling the vapors passingfrom the reaction zone, and utilizing uncondensed vapors resulting from the cooling operation as the source f of uncondensed reaction-products introduced into the mixture with said fresh quantities of hydrocarbon and oxygen.

13. A process of producing aliphatic oxygen derivatives of hydrocarbons from low boiling hydrocarbons such as occur in one of the group consisting of natural gas, reflnery gas, and natural gasoline plant vapors, and frommixtures of such hydrocarbons. which comprises continuously forming a mixture of a fresh q tity of such hydrocarbon in vapor form and a fresh quantity of air and a quantity of uncondensed reactionproducts containing a major portion of nitrogen, the quantity of uncondensed reaction-products being greater than about twenty-five times the quantity of fresh hydrocarbon and greater than about six times the quantity of fresh air, heating the mixture while under pressure in excess of 200 ypounds to a temperature above 600 F. which will initiate reaction of the oxygen with the hydrocarbon and which is favorable to the formation of aliphatic oxygen derivatives of said hydrocarbon, maintaining themixture at such temperature to cause a substantially complete combination of the free oxygen with the hydrocarbon, cooling the resulting vapors to condense reaction products therefrom, and utilizing the uncondensed vapors resulting from the cooling operation substantially free of free oxygen as the source of uncondensed reaction-products introduced into the mixture with said fresh quantities of hydrocarbon and air.

14. A process of producing aliphatic oxidation products from low boiling hydrocarbons such as occur in one of the group consisting of natural gas, refinery gas, and natural gasoline plant vapors and vfrom mixtures of such hydrocarbons, which comprises forming a mixture of a fresh quantity of such hydrocarbon in vapor form and a fresh quantity of air and a quantity of uncondensed reaction products which is-substantially free of oxygen and contains a majorproportion of nitrogen and is more than sixty times the quantity of fresh hydrocarbon, the resulting mixture containing about .5% to 3% ofuncombined oxygen, heating the mixture while under pressure in excess of 200 pounds to a temperature above 600 'F. which will initiate reaction of the oxygen with the hydrocarbon and which is favorable to the formation of aliphatic oxidation products of said hydrocarbon, maintaining the mixture at such temperature to cause a substantially complete combination of the free oxygen with the hydrocarbon, cooling the resulting vapors to condense reaction products therefrom and utilizing the uncondensed vapors resulting from the cooling operation substantially free of oxygen as the source of uncondensed reaction-products introduced into the mixture with said fresh quantities of hydrocarbon and air.

15. A process of producing aliphatic oxygen derivatives from low boiling hydrocarbons such as occur in one of the group consisting oi' natural gas, refinery gas, and natural gasoline plant vapors, and from mixtures of such hydrocarbons, which comprises continuously forminga mixture of a fresh quantity of such hydrocarbon in vapor form and a fresh quantity of air and a quantity of uncondensed reaction products which is more than about sixty times the quantity of fresh hydrocarbon, the resulting mixture containing from about 0.5% to 3% of uncombined oxygen and a major proportion of nitrogen, heating the mixture while under pressure in excess of 200 pounds to and maintaining it at a temperature favorable to the reaction of the uncombined oxygenl with said hydrocarbon to form aliphatic oxygen derivatives of said hydrocarbon, then cooling the resulting vapors to condense reaction products therefrom, and utilizing the uncondensed vapors resulting from the cooling operation as the source of uncondensed reaction products introduced into the mixture with said fresh quantities of hydro-v carbon and air.

16. A process of producing aliphatic alcohol and other oxidation products from low boiling hydrocarbons such as occur in one of the group consisting of natural gas, refinery gas, and natural gasoline plant vapors and from mixtures of such hydrocarbons, which comprises continuuously forming a mixture of a fresh quantity of such hydrocarbon in vapor form and a fresh quantity of air and a quantity of uncondensed reaction products which is more than twentylive times the quantity of fresh hydrocarbon, the

resulting mixture containing about'0.5% to 3% of uncombined oxygen and a major proportion of nitrogen, heating the mixture while under pressure infexcess of 200 pounds to and maintaining it at atemperature which effects substantially complete reaction of the free oxygen with the hydrocarbon in about three to sixty seconds until said reaction is substantially complete, then cooling the resulting vapors to condense reaction products therefrom and utilizing the uncondensed vapors resulting from the cooling operation as the source of uncondensed reaction products introduced into the mixture with said fresh quantities of hydrocarbon and air.

17. A process of producing aliphatic oxygen derivatives of hydrocarbons from low boiling hydrocarbons whichoccur in one of the group consisting of natural gas, refinery gas, and natural gasoline plant vapors, and from mixtures of such hydrocarbons, which comprises continuously forming a mixture of a fresh quantity of such hydrocarbon in vapor form and a fresh quantity of air and a quantity of uncondensed reaction products which is more than twenty-five times greater than the quantity of fresh hydrocarbon and is more than six times greater than the quantity of fresh air, heating the mixture while under a pressure of more than 200 pounds to a temperature which is favorable to the reaction of the free oxygen with the hydrocarbon to form aliphatic oxygen derivatives of said hydrocarbon and maintaining the mixture at such temperature to cause substantially complete reaction between the free oxygen and hydrocarbon, cooling the resulting vapors to condense reaction products therefrom and utilizing the uncondensed vapors resulting from the cooling operation substantially free of free oxygen as the source of uncondensed reaction products introduced into the mixture with said fresh quantities of hydrocarbo and air.

18. A process of producing aliphatic oxidation products from low-boiling hydrocarbons such as occur in one of the group consisting of natural gas, renery gas, and natural gasoline plant vapors, and from mixtures of such hydrocarbons, which comprises continuously forming a mixture of a fresh quantity of such hydrocarbon in vapor forni and a fresh quantity of air and a quantity f uncondensed reaction-products, said quantities being in such proportion th'at the mixture contains by volume 0.5% to 3% of uncombined oxygen, hydrocarbons, and a major proportion of A inert gases composed mainly of nitrogen containing relatively smaller quantities of carbon oxides, heating the mixture while under pressure in excess of 200 pounds to a temperature above about 600 F. at which said hydrocarbons react with the free oxygen tooform aliphatic oxidation products without substantial pyrolysis, maintaining the mixture at such temperature until the combination of the free oxygen is' substantially complete, cooling the resulting vapors, and utilizing the uncondense'd vapors resulting from the cooling operation as the source of uncondensed reaction-products introduced into the mixture with said fresh quantities of hydrocarbon and air. t

.CHARLES L. THOMPSON.

THOMAS -S`. BACON.

JOSEPH E. BLUDWORTH. 

